1. Field of the Invention
Embodiments of the present invention generally relate to a submerged intake screen. More particularly, embodiments of the present invention relate to a screen having a support structure. More particularly still, the present invention relates to a screen having a helical support structure.
2. Description of the Related Art
Water collection systems are typically used to provide water to end users such as manufacturing plants, cities, irrigation systems, and power generation facilities located adjacent a body of water such as a river, lake, or salt water bodies. The end users may employ this type of system as an alternative to drilling water well or buying water from a municipality. Additionally, use of these systems may be determined by the location of the end user, for example remote locations where water from a municipal source and/or electrical power to operate pumps is not readily available. These water collection systems have the ability to adapt to varying conditions and deliver water efficiently and economically.
These water collection systems typically use an inlet pipe adapted to transport water from a position submerged in the body of water to the end user adjacent the body of water. An inlet pipe is submerged in the body of water and the end of the inlet pipe is typically coupled to an intake screen which typically has a plurality of filtering members, such as ribs, mesh, or perforations disposed on its outer surface. The filtering members are configured to prevent waterborne debris and aquatic life, of a certain size, from entering the inlet pipe.
Conventional intake filter assemblies typically include an inlet pipe having an open end surrounded by and coupled to a cylindrical screen, which has a central axis that is the same as a longitudinal axis of the inlet pipe. In this way, the cylindrical screen is concentric with the inlet end of the inlet pipe. A typical intake filter assembly may also include a flow modifier pipe within the inlet pipe and extending beyond the inlet pipe into the cylindrical screen. The flow modifier pipe helps evenly distribute the flow of water through the cylindrical screen over the length of the screen.
The flow modifier pipes used now have allowed the overall length of the intake filter to increase while maintaining the intake flow rate below the maximum levels allowed. The increased length of the intake filter has caused structural problems with the intake filter. Previously the intake filters were simply welded to an end cap and a plate connected to the inlet pipe. However, the filter itself is not sufficiently strong enough to support intake and current loads when the length is increased. Attempts have been made to correct this problem using longitudinal support bars in conjunction with optional hoops which follow the filter. However, in order to brace the filter sufficiently a large number of support bars and hoops are required, increasing the overall cost and complexity of each intake filter.
Therefore, a need exist for an intake filter having a support structure which is efficient and inexpensive to build, while maximizing the strength of the filter.